html {
  background: #f7f7f7;
}
/* 内外边距通常让各个浏览器样式的表现位置不同 */
body,
div,
dl,
dt,
dd,
ul,
ol,
li,
h1,
h2,
h3,
h4,
h5,
h6,
pre,
code,
form,
fieldset,
legend,
input,
textarea,
p,
blockquote,
th,
td,
hr,
button,
article,
aside,
details,
figcaption,
figure,
footer,
header,
hgroup,
menu,
nav,
section {
  margin: 0;
  padding: 0;
}
/* 去除默认边框 */
img {
  border: 0;
}
/* 去掉列表前的标识, li 会继承 */
ol,
ul {
  list-style: none;
}
/* 来自 yahoo, 让标题都自定义, 适应多个系统应用 */
h1,
h2,
h3,
h4,
h5,
h6 {
  font-size: 100%;
  font-weight: 500;
}

* {
  -webkit-touch-callout: none; /*系统默认菜单被禁用*/
  -webkit-user-select: none; /*webkit浏览器*/
  -khtml-user-select: none; /*早期浏览器*/
  -moz-user-select: none; /*火狐*/
  -ms-user-select: none; /*IE10*/
  user-select: none;
}

input {
  -webkit-user-select: auto; /*webkit浏览器*/
}

textarea {
  -webkit-user-select: auto; /*webkit浏览器*/
}

.side-border {
  border-top: 1px solid #f1f1f1;
  border-bottom: 1px solid #f1f1f1;
}

.d-none {
  display: none;
}